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  • jdk8新特性Stream

    Stream的方法描述与实例

    1,filter  过滤

            Person p1 = new Person();
            p1.setName("P1");
            p1.setAge(10);
            Person p2 = new Person();
            p2.setName("pp2");
            p2.setAge(9);
            Person p3 = new Person();
            p3.setName("p3");
            p3.setAge(5);
            List<Person> list = new ArrayList<>();
            list.add(p1);
            list.add(p2);
    //若最后不添加collect方法,则返回类型是stream list
    = list.stream().filter(person -> person.getAge()>5).collect(Collectors.toList()); System.out.println(list); 输出结果: [Person{name='P1', age=10}, Person{name='pp2', age=9}]

     2,map

    List<String> list = Stream.of("a","b","wo").map(string -> string.toUpperCase()).collect(Collectors.toList());
    System.out.print(list);
    
    输出结果:
    [A, B, WO]

     3,mapToInt

    List<Integer> list = Stream.of("1","2").mapToInt(e ->Integer.parseInt(e)).boxed().collect(Collectors.toList());
    //maptoInt之后是IntStream类型,需要用boxed转换为Stream
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  • 原文地址:https://www.cnblogs.com/javadongx/p/8087208.html
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